Gastric cancer is the third most common cause of cancer-related death in the world (see, e.g., World Health Organization. Cancer: Fact Sheet No 297. WHO), and it remains difficult to cure in Western countries, primarily because most patients present with advanced disease. In the United States, stomach malignancy is currently the 15th most common cancer (see, e.g., Surveillance, Epidemiology, and End Results Program. SEER Stat Fact Sheets: Stomach Cancer. National Cancer Institute). In most developed countries, however, rates of stomach cancer have declined dramatically over the past half century.
Decreases in gastric cancer have been attributed in part to widespread use of refrigeration, which has had several beneficial effects: increased consumption of fresh fruits and vegetables; decreased intake of salt, which had been used as a food preservative; and decreased contamination of food by carcinogenic compounds arising from the decay of unrefrigerated meat products. Salt and salted foods may damage the gastric mucosa, leading to inflammation and an associated increase in DNA synthesis and cell proliferation. Other factors likely contributing to the decline in stomach cancer rates include lower rates of chronic Helicobacter pylori infection, thanks to improved sanitation and use of antibiotics, and increased screening in some countries (see, e.g., Global Cancer Facts & Figures, 3rd ed. American Cancer Society).
Nevertheless, gastric cancer remains difficult to cure in Western countries, primarily because most patients present with advanced disease. Even patients who present in the most favorable condition and who undergo curative surgical resection often die of recurrent disease.
Accordingly, improved methods and techniques for early detection of gastric cancer are needed.